I am receiving a error message when trying to send emails emails

Im getting this error message when I try to send emails via manager -

534: 5.7.9 Application-specific password required. For more information, go to
5.7.9 https://support.google.com/mail/?p=InvalidSecondFactor 5b1f17b1804b1-4778bae2a09sm50623915e9.0 - gsmtp

I’ve went into google but I cannot make head nor tail of what is required to fix this issue. I changed my google email password. Is this what has caused the problem?